1. Field of the Invention
The present invention relates to a stator structure of a reciprocating motor, and more particularly, to a stator structure of a reciprocating motor, which is capable of reducing the number of parts, and of simplifying assembly of the structure.
2. Description of the Background Art
In general, a reciprocating motor is formed by making the flux of a common three-dimensional motor plane. A plane moving part linearly moves on a plane according to a change in the flux formed on a plane fixed part. The reciprocating motor according to the present invention can be in a linear reciprocating motion by attaching a plurality of plane magnets to the cylindrical circumference of a stator by applying the above principle.
FIGS. 1 and 2 respectively show an example of the reciprocating motor. As shown in FIGS. 1 and 2, the reciprocating motor includes a stator S consisting of a cylindrical outer core 10 and a cylindrical inner core 20, which is inserted into the outer core 10, a winding coil 30 combined with the outer core 10 or the inner core 20 inside the outer core 10 or the inner core 20, and a moving magnet 40, which includes permanent magnets 41, and is inserted between the outer core 10 and the inner core 20 to be movable. In FIGS. 1 and 2, the winding coil is combined with the outer core.
In the above-mentioned reciprocating motor, when current flows through the winding coil 30, flux is formed around the winding coil 30 due to the current that flows through the winding coil 30. The flux forms a closed loop along the outer core 10 and the inner core 20, which form the stator S.
Because the permanent magnets 41 receive force in an axial direction due to the mutual action between the flux formed in the outer core 10 and the inner core 20 and the flux formed by the permanent magnets 41, the moving magnet 40 is in a linear motion in the axial direction between the outer core 10 and the inner core 20. When the direction of the current applied to the winding coil 30 is alternately changed, the moving magnet 40 is in a linear reciprocating motion.
The outer core 10 is comprised of cylindrical stacked core members formed by radially stacking lamination sheets 11, which are thin plates of a predetermined shape. The stacked core members are fixed by a fixing ring 12.
The cylindrical stacked core members consists of a path a, whose section is U-shaped, and triangular poles b formed in both ends of the path a. The winding coil 30 is positioned inside an opening groove H formed by the poles b and the path a. A bobbin 50 is used for forming the winding coil 30 in order to secure electrical insulation and for the convenience of fabrication. The winding coil 30 is formed by winding a coil around the bobbin 50 in multiple layers. The inner core 20 is comprised of cylindrical stacked core members formed by radially stacking lamination sheets 21, which thin plates having a predetermined shape. Because the length of the permanent magnets 41 is determined by the length of the poles b and the width of the opening groove H and the permanent magnets 41 are expensive, the poles b that determine the width of the opening groove H are triangular and the ends of the poles b form poles in order to minimize the use of the permanent magnets 41.
However, according to the above structure, because the plurality of lamination sheets 11 must be radially stacked to be cylindrical in fabricating the outer core 10 including the winding coil 30, it takes a long time to stack the lamination sheets 11. Also, because the stacked core members are fixed by the fixing ring 12 after being stacked, it takes a long time to assemble the outer core 10. Accordingly, assembly productivity deteriorates.
Also, because the outer core 10 is assembled by press fitting the fixing ring 12 in the stacked core members formed by stacking the plurality of lamination sheets 11, it is difficult to control the assembly strength of the stacked core members and to precisely process the fixing ring 12.
Therefore, an object of the present invention is to provide a stator structure of a reciprocating motor, which is capable of reducing the number of parts, and of simplifying an assembly structure.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a stator structure of a reciprocating motor, in which a bobbin 50 around which a coil 30 is wound; a plurality of unit stacked core members 61 of a predetermined thickness, each of which is formed by stacking a plurality of lamination sheets L and Lxe2x80x2 formed of predetermined shaped thin plates, and radially positioned on the outer circumference of the bobbin 50; and an injected insulator 70 combining the plurality of unit stacked core members 61 to an outer circumference of the bobbin 50.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.